1. Technical Field
The present invention relates to a novel apparatus and a method for automatically injecting fillings through multiple ports into the bottom of baked or fried goods having one or more cavities.
2. Description of Related Art
For years, bakers and confectioners have added fillings into pastries and fried goods such as eclairs, cream puffs, and doughnuts. The fillings typically comprise a viscous fluid such as jam, peanut butter, cream, mousse, caramel, or pudding. Prior art apparatuses and methods for injecting fillings into hollow or chambered goods typically involve manually operated, single-port injection devices.
Some prior art devices are as simple as a handheld, flexible, non-porous bag (such as a pastry bag) that has a stiff cone or tip capable of insertion into the food to be filled. In such a device, filling is squeezed from the bag, through the cone or tip, and into the vacant chamber or chambers of the food to be filled. Other prior art devices are semi-automated but still require a human operator to manually introduce an injection needle or nozzle into the interior of the food to be filled. They also require the operator to decide when the food has been adequately filled. For example, some prior art semi-automatic filling machines require an operator to slide a hollow food product onto a filling nozzle/needle, push a filling button to initiate filling, withdraw the product from the injecting machine as the filling is injected, and stop the filling when the product appears to have adequate filling. Other semi-automatic machines can inject a predetermined amount of filling, but the operator still must manually determine when filling is complete and must manually remove the product from the machine. Removing product too soon from such devices will result in filling being placed on the exterior of the product. It is difficult to achieve consistent filling with such devices, as they depend on the judgment and skill of a human operator. The necessity of a human operator also increases operating costs, increases the opportunity for products to be damaged, and limits the maximum speed that would otherwise be available with an automated system. Furthermore, the injection nozzles/needles on such machines are limited to fairly blunt ends and large diameters in order to protect the safety of the operators. Blunt, large-diameter injection needles leave large and unsightly filling holes in the injected food items. These larger diameters also allow filling to undesirably leak out of the product.
While several prior art references disclose automated devices for filling food items, those devices are single-port injection only and cannot be efficiently used to fill food items having multiple filling sites. For example, U.S. Pat. No. 3,871,274 granted to Hornby (the “'274 patent”) discloses a doughnut-filling device that uses a single needle to pierce the perimeters doughnuts and inject filling into their interiors. Similarly, U.S. Pat. No. 6,468,572 B2 granted to Nelson et al. (the “'572 patent”) discloses a coring and filling device that uses a single-port injector to fill nuggets. Although the '572 patent also suggests that it may be possible to inject multiple fillings either by using one depositing device to insert a mixture of different fillings or by using a separate injection device to deposit each type of filling into a single-cavity nugget, it does not offer an efficient solution for filling multi-chambered food items with a common filling.
Prior art single-port injection devices are not efficient for filling food items having multiple cavities, complex cavities or large cavities. Filling multi-chambered items with such devices requires separate single-port injection devices for each chamber or alternatively requires that each chamber be filled one at a time. It is expensive to operate separate injection devices for each chamber, and it is unduly time-consuming to fill each chamber one at a time with a single injection device. Furthermore, it is difficult to fill large or complex cavities with viscous filling using a single-port injector because higher pumping pressure is needed to force the viscous filling throughout such cavities. The higher pressures needed to distribute filling throughout large or complex cavities can undesirably damage the texture of the filling. Higher pressures also undesirably increase the tendency for filling to seep out from the injection site. Moreover, the additional handling required by this method significantly increases the opportunity for product damage.
In addition, prior art filling devices that inject filling from above, such as a device in accordance with the '572 patent, or from the side (or perimeter), such as a device in accordance with the '274 patent, leave unsightly filling holes that remain visible when the product is viewed from above or from a side.
Consequently, a need exists for an automatic food-filling device having a multi-port filling head that is capable of filling single-chambered and multi-chambered food items from the bottom. Such a device should be able to inject a predetermined amount of filling into the chambered food item. Such a device should also be able to divide a flow of filling among multiple injection needles so that each chamber of a multi-chambered food item can be simultaneously filled with at least one needle per chamber. Alternatively, such a device should be able to quickly and efficiently fill a food item having a large or complex cavity by simultaneously injecting filling through two or more injection needles that are attached to the same filling head. Furthermore, by filling food items from the bottom, such a device should be able to fill food items without leaving unsightly injection holes that are visible from above or from the side. Automatic filling from the bottom will also reduce the occurrence of product damage due to operator handling.